Get rid of get file path by using the data.json convention to store the challenge information (#67)

Signed-off-by: Merwane Hamadi <merwanehamadi@gmail.com>

agbenchmark/tests/basic_abilities/read_file/data.json

@@ -0,0 +1,20 @@
+{
+  "name": "basic_read_file",
+  "category": ["basic"],
+  "task": "Write the string 'random string' before any existing text to the file called file_to_check.txt",
+  "dependencies": ["basic_write_file"],
+  "ground": {
+    "answer": "random string Hello World!",
+    "should_contain": ["random string", "Hello World!"],
+    "files": ["file_to_check.txt"],
+    "type": "file"
+  },
+  "mock": {
+    "mock_func": "basic_read_file_mock"
+  },
+  "info": {
+    "description": "This reads the file quickly",
+    "difficulty": "basic",
+    "side_effects": [""]
+  }
+}